Timestamp when item has changed

[jonatanhov (Jonatan Hovgaard)]

I have definded a “lastupdate” item for each of my oudoor hue motion sensors. The idea was to set a timestamp every time a motion has been detected. By doing that I will be able to see when the last motion was detected on each motion sensor. The problem is that it seems like the “ParkingHueMotion_Occupancy” is updated with the same value everytime the hue sensor is reporting a temperature or lux change. I will like to update the timestamp only when “ParkingHueMotion_Occupancy” is changed from “false” to “true”.

Any suggestion on how to do that? If not, is there any other way to retrieve a timestamp from when an item was changed last time?

Rule example:

configuration: {}
triggers:

• id: “1”
  configuration:
  itemName: ParkingHueMotion_Occupancy
  type: core.ItemStateUpdateTrigger
  conditions:
  actions:

• inputs: {}
  id: “2”
  configuration:
  type: application/vnd.openhab.dsl.rule
  script: |2-

       ParkingHueMotion_LastMotion.postUpdate(new DateTimeType())
  

  type: script.ScriptAction

[jonatanhov (Jonatan Hovgaard)]

I tried to change it to the following (adding a condition). I hope this will solve my problem.

configuration: {}
triggers:

• id: “1”
  configuration:
  itemName: EntranceHueMotion_Occupancy
  type: core.ItemStateChangeTrigger
  conditions:

• inputs: {}
  id: “3”
  configuration:
  itemName: EntranceHueMotion_Occupancy
  operator: =
  state: “true”
  type: core.ItemStateCondition
  actions:

• inputs: {}
  id: “2”
  configuration:
  type: application/vnd.openhab.dsl.rule
  script: |2-

       EntranceHueMotion_LastMotion.postUpdate(new DateTimeType())
  

  type: script.ScriptAction

[jimtng]

Starting from openhab 5.0 every item has a built in timestamp of last update and last change

https://github.com/openhab/openhab-core/pull/4351

It is also available in rulesdsl event:

Textual Rules

[jonatanhov (Jonatan Hovgaard)]

Sounds interesting. I have tried to find script examples (DSL/Javascript), but without any luck. Also the documentation of getLastStateChange is very sparse.

[jimtng]

It’s quite simple. In your rulesDSL, ParkingHueMotion_Occupancy.lastStateChange will give you a ZonedDateTime

I am not familiar with jsscripting, but open Item - openHAB JS and search for “laststatechange” you’ll see the method name.

in JRuby it’s just ItemName.last_state_change which returns a ZonedDateTime much like in DSL.